Parametric Galvo Laser Centering Guide

Motivation

Sometimes I want to recenter workpieces on my galvo laser's blue light so that I can quickly swap them out and rerun the laser operation from the controller instead of reframing and sending a new job from the laser software.

I needed a simple tool that could quickly locate the center of the workpiece then line up with the blue light – all while at the laser.

Solution

Design and laser cut a centering guide to accomplish the following objectives:

• Fully parametric providing customization of all dimensions and tolerances

• Compatibility with UltraJig accessories (mainly Shifters) to center the guide on the workpiece from one or both sides of the centerpoint

• Pull tab to retain the UltraJig accessories and improve ergonomics for sliding them

• Index markings to aid proper UltraJig accessory positioning with different engraving depths and markings for 1, 5, and 10 mm increments

• Blue light visible on the centering guide for rough placement that disappears only when the guide is optimally centered

• Support workpieces up to 200 mm

• Holes for hanging the guide when not in use

Design

• There is an opaque center zone with a small hole that reflects the blue light until it is allowed to pass through the guide indicating the guide is centered on the blue light.

Customization

The Fusion files are included. You can customize the parameters (DESIGN | SOLID | MODIFY | Change Parameters) as necessary. When you open the Parameters dialog, first sort by name. The parameters most optimized for customization are favorited and commented in detail to help you. The non-favorited parameters should work as well but may require more tinkering to repair broken downstream features.

I anticipate most people will cut the guide out of 3 mm clear acrylic and engrave using the provided .svg and/or .xcs files (available on Atomm). For those who want to further customize the indices or any other aspect of the laser project, I have also provided the Illustrator file. I highly recommend the SplitPath script to remove all the unnecessary score paths using the cut paths.

Let me know (Messenger | Printables.com) if you have any questions.

Materials

• Acrylic, Clear, 3.0 mm thick. Alternatively, almost any other rigid material could work as well. 3.0 mm is the ideal thickness for accessory compatibility.

Laser Scoring, Engraving, and Cutting

The xTool Studio (.xcs) files containing the graphics and my settings are on Atomm.

Important –The included laser paths represent the final result, so adjust inward for kerf. The slots are especially important to nail down the fitment so that the accessories slide smoothly while maintaining proper alignment.

I processed the laser job on an xTool P2, but the paths will fit on an F2 Ultra plate diagonally as well. If you do this, please let us know how it turns out by posting your make!

Printing

See the attached .3mf for my pull tab settings and model orientation. Reference the UltraJig post for printing accessories.

• Parts

  • Recommended

    • (1-2 as needed) UltraJig Accessory

    • Shifters position and center workpieces along the XY plane, so will probably be the most useful but risers could also prove helpful for centering on some objects

    • (1 per accessory) Pull tab

  • Alternative to laser for the centering guide

    • The centering guide can be printed, so I am including the model file as well. I did not prototype this project with a printed guide, so I am not including the .gcode for it, but it is included in the PrusaSlicer project file with 100% perimeters. If you do print the guide and the tolerances are off, please let me know and we can work together on it (Messenger | Printables.com).

    • I designed and prototyped the accessories on a Prusa CORE One

Post-Processing

     Printed Parts

1. Accessories – The pegs should be cleaned up before attempting to install on the centering guide

2. Similarly, clean up and smooth out any inconsistencies in the pull tab channel before attempting to connect to an accessory

Installation

1. Thoroughly clean up the accessory and pull tab (see post-processing above)

2. Insert the accessory in the centering guide slots. You may prefer the accessory on the engraved or smooth side depending on the material you used for your centering guide.

3. Place the assembly with the pegs facing up on a flat surface

4. Important – Some of the accessories (e.g., Shifters) are printed with the pegs oriented vertically. This means the only thing holding those features together is layer adhesion which is usually the weakest part of a 3D Print. If you encounter more than slight resistance, you should remove the pull tab and clean up the parts more before proceeding. The pull tab can be installed with the larger protrusion facing toward or away from the center. Carefully and slowly place the pull tab on the pegs and press it on 1-2 layer lines at a time per peg until it is fully snapped on and touching the centering guide. The pull tab has a slight draft angle which makes the fitment tighter the more it is installed. This helps to minimize the chance of it getting stuck on the peg while also providing for a secure fit when installed.

Operation

Self-explanatory, but let me know if you have any questions (Messenger | Printables.com).

Removal

The pull tab has chamfers around each peg slot. To uninstall, place the centering guide assembly on a flat surface with the pull tab facing up. Using your fingers, carefully pry the pull tab up on both ends as evenly as possible to avoid applying a bending force to the accessory pegs.

Questions

Please let me know if you have any questions (Messenger | Printables.com).

Shameless Plug

If this model helped you solve a problem, save some time, or in any way made your life a little easier then please consider clicking the Like button and posting your Makes! If it fell short after clicking on the title of the model, please let me know (Messenger | Printables.com). Either way, Thank you!